This application is fine for a couple of users, I've set up several PIX's this way using IPSec.
For more security and to make life easier handling more remote access clients I would recommend using a RADIUS server for the authentication.
One point that frequently comes up in this forum, you will not be able to connect in using the remote access client and connect to a site across the site to site VPN, the PIX will not currently allow this.
Andy